Experimental demonstration of indoor uplink near-infrared LED camera communication.

In this paper, we present experimental demonstration of an indoor uplink near-infrared LED camera communication (ICC) that employs near-infrared (IR) light as a communication medium and a camera as the receiver. The proposed ICC exploits advantages of the camera receiver to provide wider coverage and accurate indoor positioning in IR communications. Since near-IR light is the communication medium, ICC can safely increase the light intensity compared with other visible light based wireless communication schemes. Unlike previous studies focused on positioning only, the ICC provides practical uplink indoor wireless communication as well as positioning. As in optical camera communications, the blooming effect from slow speed cameras needs to be mitigated in the ICC. An adaptive intensity compensation algorithm is also proposed for reducing this blooming effect. The blooming reduction algorithm is based on the absence of visible light interference in IR communications. Experiments demonstrate that employing an even low-specification webcam and low-power LEDs can provide centimeter-scale accuracy for the user positioning and a data rate of 6.72 kbit/s at a distance of 100 cm.